According to Wikipedia, more than 12, 000 dust particles accumulate in a locked apartment. The amount of dust increases throughout the year: in the beginning there is little, and further to the end of the year there is a lot of dust. Soil, glass, sand, and soot particles — all of these settle on the surfaces, including our houses. This calendar is dedicated to the problem of air pollution with dust. Every month a new type of dust is added to the air.
